Male and Female Reproduction

Spermatid

An immature sperm cell produced from a spermatocyte during spermatogenesis. Undergo maturation to become fully functional spermatozoa.

Epididymis

A coiled tube located on the back of each testis where spermatids mature and are stored before ejaculation.

Caput

the head region of the epididymis where sperm maturation begins.

Corpus

the middle section of the epididymis where sperm continue to mature and are stored.

Cauda

the tail region of the epididymis where sperm are stored until ejaculation.

Fibroelastic

Extends with help of sigmoid flexure

Vascular/Musculuocavernous

Blood sinusoid more prvelent than connective tissues

Corpus Luteum Regression

The process by which the corpus luteum, formed after ovulation, degenerates if pregnancy does not occur, leading to decreased progesterone levels.

Corpus Hemorrhagicum

blood clot that forms if blood vessels rupture during ovulation

Corpus Luteum

A hormone-secreting structure formed from the remnants of the follicle after ovulation that produces progesterone to maintain the uterine lining.

Corpus Alibcan

A fibrous scar tissue that replaces the corpus luteum after its regression, indicating the end of the luteal phase.

Monoestrus

Referring to species that have only one estrous cycle per breeding season, typically characterized by a single period of receptivity for mating.</span>

Polyestrus

Referring to species that experience multiple estrous cycles within a single breeding season, allowing for several opportunities for mating.

Anestrus

A reproductive state in which an animal does not exhibit estrous cycles or shows little to no signs of sexual receptivity, often occurring during specific seasons or due to environmental factors.

Primordial Germ Cell

The earliest stage of germ cell development, which eventually gives rise to sperm or ova during gametogenesis. Primordial germ cells migrate to the developing gonads where they differentiate into gametes.

Follicular Cells

Specialized cells in the ovarian follicles that support the development of oocytes and secrete hormones such as estrogen.

Oogenesis

The process of female gamete (ova) formation, which involves the growth and maturation of ovarian follicles and ultimately leads to ovulation.

Inhibins

hormones produced by the ovaries and testes that inhibit the secretion of follicle-stimulating hormone (FSH) from the pituitary gland, playing a role in regulating reproductive functions.

Monotocous

One offspring at one time, one ovum released per cycle

Polytocous

Refers to the production of multiple offspring at one time, with several ova released per cycle.

Luteinization

Granulosa cells respond to LH surge by transforming from estrogen to progesterone producing cells.

Acrosome

A cap-like structure on the head of a sperm cell that contains enzymes essential for fertilizing an egg, allowing it to penetrate the outer layers of the ovum (egg)

Polar Bodies

Small cells produced during oocyte development that contain little cytoplasm and are typically not viable.

Pituitary Hormone Effects

LH and FSH stimulate spermatogenesis and testosterone secretion by the testes

Testes hormone effects

Testosterone and inhibin inhibit the secretion of GnRH by the hypothalamus and LH and FSH by the pituitary

LH for males

Glycoprotien hormone, stimulates the Leydig cells in the testes to produce testosterone, which is necessary for sperm production

LH for femlaes

inducing ovulation (egg release) and supporting the conversion of the ruptured follicle into the corpus luteum, which produces progesterone

FSH for males

FSH stimulates the testes to produce sperm

FSH for females

FSH promotes the growth of ovarian follicles in the ovaries before ovulation and triggers the production of estrogen.

GnRH

Stimulates LH and FSH production

Dihdrotestosterone

A potent androgen that plays a key role in the development of male physical characteristics and reproductive function, binds to intracellular receptors

Testosterone

A steroid hormone produced primarily in the testes, responsible for the development of male reproductive tissues and secondary sexual characteristics.

Theca Cells

Layer of stromal cells surrounding granulosa, develops during the secondary follicular stage

Granulosa

Become several layers thick producing group of cells

Zona pellucida

Protective shell provided via cross linked glycoproteins produced from granulosa

Thecal cells + LH

Proliferation and production of androgens (sex hormones)

Granulosa cells + LH

Proliferation and development of enzymes used to convert androgens

Capacitation

Process that conveys that capacity to fertilize the ovum

When does insemination occur

Prior to ovulation so that viable spermatozoa are present when ova arrive for fertilization

Zona Pellucida

Semipermeable membrane made of glycoproteins, contains receptor sites for attachment of sperm and ZP3

Gestation

The period of development of the embryo and fetus inside the uterus from conception until birth.

Step 1 of gestation

Fertilization and early embryonic development- occurs in lumen of female reproductive tract

Step 2 of Gestation

Implantation of the embryo into the uterine wall, followed by the formation of the placenta for nutrient exchange.

Step 3 of Gestation

Placentation, or development of the placenta- involves development of fetal membranes

Step 4 of Gestation

Fetal growth

Implantation

Attachment of a blastula to the uterine epithelium and penetration of the epithelium by embryonic tissue, non invasive, result of formation of cell to cell junctions between embryonic tissues and uterine epithelium

Migration

Occurs in lumen before implantation, permits the spacing of embryos, contact or paracrine communication between embryos occurs.

Amnion

Innermost layer of placenta, surrounds fetus

Allantois

Sac membrane the surrounds placenta, middle layer

Chorion

Outer layer of placenta, attaches to lining of uterus

Relaxin

Hormone present in pregnancy that prepares for parturition by opening cervix and relaxing ligaments and bones around the birth canal.

Uterine Involution

Starts immediately after parturition, myometrium and uterus contracts after placenta is released to reduce blood loss.